Posted: 2007.02.02(Fri)21:35 Post subject: New fish not happy!
I have just introduced a small school of 6 Rasbora hengeli into my tank. Immediately they began hovering just under the surface of the tank as though there is not enough oxygen, they have now been this way for three hours. Let me tell you about my tank:
60L, 60cm: Established over two years.
Filter: Eheim (2008) internal, cretes a good current accross the surface of the water.
Plants: Pennywort, Ambulia, dwarf swords, Anubius, Crypts, Liliopsis, duckweed.
Driftwood, water is mildly tannin stained.
Other inhabitants: Male and female adult Bristlenose catfish.
Ammonia, nitrites: negligable
pH: Approx 6.5, water very soft.
Temp: 26 C
No CO2 injection
Strong lighting, currently switched off, runs approx. 1.30pm to 1.30am (I live in a hot place so don't run it all day).
The pH in the pet shop was approx. 7 - 7.2. I acclimatised the fish by turning down the sides of the bag and slowly introducing tank water (to approximately double or triple the original water in the bag) over a half hour time period before letting them into the tank. In the shop they were fine, in the bag they were fine, even with the new water being added. The bristly's were fine but just before the lights came on one of them had a gulp of air also.
Could it be the pH change causing this? Could this just be a stress reaction? Could it be that oxygen is low as the plants aren't respirating in the dark? Should I turn the lights back on? This hasn't happened before and I am very worried. Can anyone shed any light?
Update: the lights are on, the Rasbora's are still hovering in a corner gulping for air, a while ago one jumed through a corner in the hood, luckily I was there to pop it back in. I have accepted that this is an oxygen problem, how do I change this quickly? The tank isn't over-populated, there are plants, the surface of the tank is being agitated (I've even increased this), and the water parameters are OK. Help!!
Yes, do you have an air pump? Adding a few airstones should help.
When the lights are off, the plants take in oxygen as well, combined with the extra oxygen needed (adding new fish, this would explain why it has never occured before) would cause this.
Try to make as much surface aggitation as possible, experiment a bit with the filter outlet.
So when the lights are on they should be OK with the plants not taking up any oxygen, and actually making some.
But you will need to get more oxygen in the water, a couple of air stones attached to a strong air pump is probably the best way to do this.
Get the pump as soon as possible if you don't have one. And leave the lights on until you can get one.
That's really bizarre. It is possible that it's some form of pH shock, but the symptoms don't really match up. I would go ahead and add an airstone. Otherwise, I can't think of anything other than waiting and keeping your fingers crossed. I've never seen that kind of behavior in a well-aerated tank before. I'm sorry I can't think of anything else. _________________ Am I obsessed? Wait a minute... don't answer that!
Do you do frequent water changes? - What are your nitrates, if high, they are toxic. Also, if the hardness/softness difference between your tank and the lfs, is very big, that could be giving the fish trouble breathing.
Check your nitrates, if they are over 40, do a water change - at least 20% if you do water changes once every 2-3 weeks. If you don't, than you'll have trouble because your existing fish will have become used to the poor water quality. (Catfish are messy messy). Also, a 15g isn't very much space for them.
So, if you don't do water changes much, change 10% every day until the nitrates are under 20. You might loose the raspboras. Sounds kind of like you have Old Tank Syndrome.
Thanks guys, nitrates are 5, not a prob, sorry I didn't mention. I do regular water changes, tank was empty (other than bristly's) for three weeks before these guys went in. During that time I renovated, replaced plants and added some new driftwoood. I didn't replace the water other than water changes and all water tests have been fine. I can't find anything other than disease (which I'm pretty sure they don't have at this time) or oxygen shortage that would cause this kind of behaviour. The bristly's too are still hanging close to the surface.
Don't understand why adding new fish would suddenly cause an oxygen shortage, it's either there or it isn't, isn't it?
Do airstones make a difference in a tank which already has good surface agitation? I would have thought not, I've never used or needed one in the past but...
This experience kind of has me questioning myself and what I thought I knew. I found myself so stressed that I had to go and catch a movie to get away from tank gazing for a while. I know these guys are sensitive, but I expected them to hide for a while, not this drama.
I so hope these guys make it, they are truly the most amazing fish, I'm a bottom feeder kind of gal but I might be changing my spots!
It's now 10.5 hours since introducing them. The lights have been on for about 8.5 hours. The Rasbora's are still hanging around the surface but are taking short breaks from this to wizz around the tank at break neck speed (they're very cool). This I see as a slightly possitive sign but I am very hesitant to get my hopes up and still anxious as the lights will go off again in a few hours. I haven't fed them yet as I'm concerned that feeding them might just increase their need for O2 (if they eat that is), maybe I'll try a little. So stressful...
If people really think that an airstone is the solution I'll get one in the morning (if they're still alive and short on O2 that is). One other thing. I thought airstones were a bit of a no no in planted tanks? The more surface agitation (of which there is already plenty) the more CO2 gets lost. Yes? No? Maybe?
Any other new or wonderful suggestions? Thanks for those so far.
You cannot post new topics in this forum You cannot reply to topics in this forum You cannot edit your posts in this forum You cannot delete your posts in this forum You cannot vote in polls in this forum